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191.
The effects of Tasco®, a product made from the brown seaweed (Ascophyllum nodosum) were tested for the ability to protect Caenorhabditis elegans against Pseudomonas aeruginosa infection. A water extract of Tasco® (TWE) reduced P. aeruginosa inflicted mortality in the nematode. The TWE, at a concentration of 300 µg/mL, offered the maximum protection and induced the expression of innate immune response genes viz.; zk6.7 (Lypases), lys-1 (Lysozyme), spp-1 (Saponin like protein), f28d1.3 (Thaumatin like protein), t20g5.7 (Matridin SK domain protein), abf-1 (Antibacterial protein) and f38a1.5 (Lectin family protein). Further, TWE treatment also affected a number of virulence components of the P. aeuroginosa and reduced its secreted virulence factors such as lipase, proteases and toxic metabolites; hydrogen cyanide and pyocyanin. Decreased virulence factors were associated with a significant reduction in expression of regulatory genes involved in quorum sensing, lasI, lasR, rhlI and rhlR. In conclusion, the TWE-treatment protected the C. elegans against P. aeruginosa infection by a combination of effects on the innate immunity of the worms and direct effects on the bacterial quorum sensing and virulence factors. 相似文献
192.
Primary amoebic meningoencephalitis is an acute disease of the central nervous system of humans and animals caused by Naegleria fowleri. This report describes a case of meningoencephalitis caused by N. fowleri in a crossbred, one-year-old bovine with progressive neurological signs. At necropsy there was thickening of the meninges and multifocal areas of malacia in the thalamus, caudal and rostral colliculi, parietal and occipital cortex, and cerebellum. Histologically there was multifocal necrosupurative meningoencephalitis associated with areas of malacia containing amoebic trophozoites. Immunohistochemistry of the brain was positive for N. fowleri. The disease should be included among the differential diagnosis of diseases of the central nervous system in cattle in areas where animals are exposed to hot, stagnant water. 相似文献
193.
194.
Mee J 《Irish veterinary journal》2010,63(4):230-235
The decline in dairy herd fertility internationally has highlighted the limited impact of traditional veterinary approaches to bovine fertility management. Three questionnaire surveys were conducted at buiatrics conferences attended by veterinary practitioners on veterinary dairy herd fertility services (HFS) in countries with a seasonal (Ireland, 47 respondents) and non-seasonal breeding model (The Netherlands, 44 respondents and Portugal, 31 respondents). Of the 122 respondents, 73 (60%) provided a HFS and 49 (40%) did not. The majority (76%) of all practitioners who responded stated that bovine fertility had declined in their practice clients' herds with inadequate cow management, inadequate nutrition and increased milk yield as the most important putative causes. The type of clients who adopted a herd fertility service were deemed more educated than average (70% of respondents), and/or had fertility problems (58%) and/or large herds (53%). The main components of this service were routine postpartum examinations (95% of respondents), fertility records analysis (75%) and ultrasound pregnancy examinations (69%). The number of planned visits per annum varied between an average of four in Ireland, where breeding is seasonal, and 23 in Portugal, where breeding is year-round. The benefits to both the practitioner and their clients from running a HFS were cited as better fertility, financial rewards and job satisfaction. For practitioners who did not run a HFS the main reasons given were no client demand (55%) and lack of fertility records (33%). Better economic evidence to convince clients of the cost-benefit of such a service was seen as a major constraint to adoption of this service by 67% of practitioners. 相似文献
195.
Thomas A. Spies Thomas W. Giesen Frederick J. Swanson Jerry F. Franklin Denise Lach K. Norman Johnson 《Landscape Ecology》2010,25(8):1185-1199
Conserving biological diversity in a changing climate poses major challenges for land managers and society. Effective adaptive
strategies for dealing with climate change require a socio-ecological systems perspective. We highlight some of the projected
ecological responses to climate change in the Pacific Northwest, U.S.A and identify possible adaptive actions that federal
forest managers could take. The forest landscape, ownership patterns and recent shift toward ecologically based forest management
provide a good starting place for conserving biological diversity under climate change. Nevertheless, undesirable changes
in species and ecosystems will occur and a number of adaptive actions could be undertaken to lessen the effects of climate
change on forest ecosystems. These include: manipulation of stand and landscape structure to increase ecological resistance
and resilience; movement of species and genotypes; and engaging in regional, multi-ownership planning to make adaptive actions
more effective. Although the language and goals of environmental laws and policies were developed under the assumption of
stable climate and disturbance regimes, they appear to be flexible enough to accommodate many adaptive actions. It is less
certain, however, if sufficient social license and economic capacity exist to undertake these actions. Given the history of
contentious and litigious debate about federal forest management in this region, it is likely that some of these actions will
be seen as double-edge swords, spurring social resistance, especially where actions involve cutting trees. Given uncertainties
and complexity, collaborative efforts that promote learning (e.g. adaptive management groups) must be rejuvenated and expanded. 相似文献
196.
197.
Mary T. Franklin 《EPPO Bulletin》1972,2(6):5-15
The genus Meloidogyne includes 32 species. The main character used for differentiation is the posterior cuticular pattern of the female. This is difficult to define and often variable but in most species it is characteristic. The body length and length and shape of the tails of the larvae, and the head characters of males, can also be used in identification of some species. The morphological and physiological variability in the commonest species is so great as to suggest that they may be species complexes or that evolution may be proceeding at an observable rate. This results in some uncertainty in the systematics. 相似文献
198.
The effects of future urban development on habitat fragmentation in the Santa Monica Mountains 总被引:8,自引:0,他引:8
A site suitability model of urban development was created for the Santa Monica Mountains in southern California, USA, to project to what degree future development might fragment the natural habitat. The purpose was to help prioritize land acquisition for the Santa Monica Mountains National Recreation Area and examine to what extent projected urban development would affect distinct vegetation classes. The model included both environmental constraints (slope angle), and spatial factors related to urban planning (proximity to roads and existing development, proposed development, and areas zoned for development). It implemented a stochastic component; areas projected to have high development potential in the suitability model were randomly selected for development. Ownership tracts were used as the spatial unit of development in order to give the model spatial realism and not arbitrarily `develop' grid cells. Using different assumptions and parameters, the model projected the pattern of development from 5 to 25 years hence (based on recent development rates in the area). While <25% of the remaining natural landscape is removed under these scenarios, up to 30% of core (interior) habitat area is lost and edge length between natural vegetation and development increases as much as 45%. Measures of landscape shape complexity increased with area developed and number of patches of natural habitat increased four- to nine-fold, depending upon model parameters. This increase in fragmentation occurs because of the existing patterns of land ownership, where private (`developable') land is interspersed with preserved park lands. 相似文献
199.
Central core myopathy in a great dane 总被引:3,自引:0,他引:3
M. P. Targett R. J. M. Franklin N. J. Olby J. Dyce J. R. Anderson J. E. F. Houlton 《The Journal of small animal practice》1994,35(2):100-103
An eight-month-old female great dane was referred for investigation of exercise intolerance that had developed progressively over one month. Examination revealed poor muscle mass, elevated plasma levels of muscle-associated enzymes and electromyographic abnormalities. The dog was euthanased at 15 months old because of severe exercise intolerance. Tissue obtained by biopsy and at post mortem examination revealed prominent well defined central core structures within most muscle fibres, but no other abnormalities. The condition was diagnosed as a central core myopathy. 相似文献
200.